<template>
  <view>
    <!-- <my-search @click.native="onSearch"></my-search> -->
    <my-search @click="onSearch"></my-search>
    <view class="scroll-view-container">
        <!-- 左侧的滚动视图区域 -->
        <scroll-view class="left-scroll-view" scroll-y :style="{height: wh + 'px'}">
          <block v-for="(item,index) in cateList" :key="index">
            <view class="left-scroll-view-item" :class="active === index?'active':''" @click="activeChanged(index)">{{item.cat_name}}</view>
          </block>
        </scroll-view>
        <!-- 右侧的滚动视图区域 -->
        <scroll-view :scroll-top="scroolTop" class="right-scroll-view" scroll-y :style="{height: wh + 'px'}">
          <view class="cate-lv2" v-for="(item2,index2) in cateLevel2" :key="index2">
            <view class="cate-lv2-title">/{{item2.cat_name}}/</view>
            <!-- 二级分类下的三界分类列表 -->
            <view class="cate-lv3-list">
              <view class="cate-lv3-item" v-for="(item3,index3) in item2.children" :key="index3" @click="gotoGoodsList(item3)">
                <image :src="item3.cat_icon"></image>
                <text>{{item3.cat_name}}</text>
              </view>
            </view>
          </view>
        </scroll-view>
      </view>
  </view>
</template>

<script>
  import badgeMix from '@/mixins/tabbar-badge.js'
  export default {
    data() {
      return {
        // 窗口的可用高度 = 屏幕高度 - navigationBar高度 - tabBar 高度
        wh: 0,
        // 分类数据列表
        cateList: [],
        // 当前选中项的索引，默认让第一项被选中
        active:0,
        // 二级分类
        cateLevel2:[],
        scroolTop:0
      };
    },
    mixins:[badgeMix],
    onLoad() {
      // 获取当前系统的信息
      const sysInfo = uni.getSystemInfoSync()
      // 为 wh 窗口可用高度动态赋值
      this.wh = sysInfo.windowHeight-50
      // 调用获取分类列表数据的方法
      this.getCateList()
    },
    methods:{
      async getCateList() {
        // 发起请求
        const { data: res } = await uni.$http.get('/categories')
        // 判断是否获取失败
        if (res.meta.status !== 200) return uni.$showMsg()
        // 转存数据
        this.cateList = res.message
        // 二级分类数据
        this.cateLevel2 = this.cateList[0].children
        console.log(res)
      },
      // 切换分类
      activeChanged(index){
        this.active = index
        this.cateLevel2 = this.cateList[index].children
        // 当右侧分类栏滚动到最底部时 点击另一分类时 滚动条没有归零
        this.scroolTop = this.scroolTop ? 0 : 1
      },
      // 跳转页面
      gotoGoodsList(item){
        uni.navigateTo({
          url:'/subpkg/goods_list/goods_list?uid='+item.cat_id
        })
      },
      //
      onSearch(){
        // console.log('my name is cate')
        uni.navigateTo({
          url:'/subpkg/search/search'
        })
      }
    }
  }
</script>

<style lang="scss">
.scroll-view-container {
  display: flex;

  .left-scroll-view {
    width: 120px;

    .left-scroll-view-item {
      line-height: 60px;
      background-color: #f7f7f7;
      text-align: center;
      font-size: 12px;

      // 激活项的样式
      &.active {
        background-color: #ffffff;
        position: relative;

        // 渲染激活项左侧的红色指示边线
        &::before {
          content: ' ';
          display: block;
          width: 3px;
          height: 30px;
          background-color: #c00000;
          position: absolute;
          left: 0;
          top: 50%;
          transform: translateY(-50%);
        }
      }
    }
  }
  .cate-lv2-title {
    font-size: 12px;
    font-weight: bold;
    text-align: center;
    padding: 15px 0;
  }
  .cate-lv3-list{
    display: flex;
    flex-wrap: wrap;
    
    .cate-lv3-item{
      width: 33.33%;
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      margin-bottom: 10px;
      
      image{
        width: 60px;
        height: 60px;
      }
      text{
        font-size: 12px;
      }
    }
  }
}
</style>
